Concrete Inspection – NOW OFFERING DRONES INSPECTION
BCRC are experts in inspection, testing and assessment of concrete structures. Because we are engineers, we understand how structural behaviour impacts on selection of test areas. We are also experts in concrete durability, so we know how the exposure and structure interact and what is critical to service life. We have over 30 years of experience in structural surveys, so we understand logistics and the importance of planning and regimented data acquisition. We have been instrumental in developing Non-Destructive Test (NDT) methods and have excellent relations with the world’s leading suppliers of NDT Equipment. We also sit on the committees writing the codes and recommended practices that define how surveys should be undertaken.
Need a company that really understands structural surveys? Contact BCRC.
We can plan and undertake surveys initiated for any reason, i.e.
- Condition assessment to determine repair requirements
- Inspection and testing for finish class assessment
- Testing for structural assessment
- Pre-purchase condition assessment
- Routine inspections
Survey Planning
Establish Client Requirements
BCRC use their expertise to advise the client on appropriate testing depending on the outcomes sought, safety requirements, reliability requirements, maintenance plans and commercial aspects that may affect his business.
Review Exposure
BCRC quickly establish the exposure by reviewing design, construction and operational activities (past and present). In many cases the important parameters are immediately obvious (e.g. in splash zones of marine structures the problem is probably chlorides) while in others a cursory evaluation could be misleading.
Design Analysis
Clues to the cause of deterioration can often be found in the design. For example, tension regions may have micro-cracking and have poorer penetrability. It is important to understand how the structure is working if critical areas are to be identified.
Construction Assessment
In some cases, construction assessment goes far beyond looking at detailing (e.g. construction joints). It may be necessary to review materials used (e.g. contaminated aggregates), establish seasonal influences (e.g. effect of curing) and review techniques used (e.g. compaction). In some cases, it may be necessary to review construction records and discuss the method used with the contractor or owners’ representatives.
Logistics
Logistical planning is critical to the success of surveys. In some cases, it may simply be a case of walking up to the surface and making observations, in others erecting access and catching a short weather window at a remote location may all but be impossible. Our survey managers have planned surveys from the North Sea to the remote regions of Northern Australia and can ensure the work is undertaken with the minimum of down time.
Inspection and Testing
Our survey managers are expert in sampling, non-destructive testing and laboratory analysis. As such they manage the inspection and testing programme.
Standards
Standard classification systems are used for classification of reinforcement corrosion extent and concrete defect type and size. A major issue with visual surveys is that inspectors give subjective assessments. A wide crack to one inspector may be a fine crack to another. Only by using standard terms are consistent results obtained.
Proforma, prepared in the planning stage, show significant design or construction features. Survey results can be quickly and accurately recorded on the proformas.
Testing is undertaken to defined standards to ensure results obtained can be interpreted in an appropriate fashion.
Extent of Testing
The extent of testing needs to be carefully planned. Too few samples and the confidence level in results is low. Too much testing and the survey is overly expensive. It is also important to test in an appropriate order so that broader spread tests can help indicate where more detailed tests are required.
Sampling
BCRC know how to take samples to minimise the risk of contamination and to take samples so as not to damage the structure and so the samples are representative. Cores, drilling dust, soils and water samples are all taken in accordance with standards to ensure no cross contamination, appropriate sample size and correct labelling.
NDT’s
Our experts have been involved in non-destructive testing for over 30 years. In some cases, they were involved in the pioneering development of some of today’s common test. Test methods that we commonly use and can provide methods statements on include:
Visual inspection
- visual by remote viewing, e.g. drone inspection
- crack width
- crack movement
- drummy testing
Corrosion surveys including
- Reinforcement electrical potentials using rapid scan Canin and potential wheel
- Carbonation and chloride penetration site test
- Concrete resistivity for corrosion rate
- Corrosion rate by linear polarisation and logging using embedded probes
- Cover survey pulsed eddy current and radar
Concrete assessment including
- Pendulum hammer 1-10MPa strength test (P14)
- Digital Schmidt hammer tests (P15)
- Karsten tube absorption test for concrete quality and coating effectiveness (P16)
- Impact echo for defects & concrete thickness (P17)
- Impulse response for change to local structural response to detect defects
- Ultrasonic pulse echo technique for concrete thickness and defect identification
- Radar (GPR) for location of deep reinforcement (including prestressing), buried objects & prestressing
- Thermography for location of delaminations
- Pull off testing for veneers, overlays, carbon fibre strengthening, coatings & shotcrete (P18)
- Extraction testers (P19)
- Concrete sampling by coring, jack hammering and dust collection (P20-24))
- Interferometric radar for deflection and vibration analysis
Monitoring
In some cases, the structures condition cannot be immediately determined as load or environment can have cyclic effects. We can determine the appropriate monitoring systems and manage installation, monitoring and assessment systems.
Readily available monitoring systems include:
- linear polarisation
- displacement transducers
- potential cell
- rack probes
- strain gauges
- temperature measurement.
All can be incorporated into web-based monitoring.
Assess Results
In many cases, the cause of deterioration is simple to establish. However, secondary effects can have significant implications on the long-term prognosis. It may be necessary to undertake a range of check tests to determine if mechanisms other than the obvious are occurring.
The survey should establish the extent of deterioration so that the most effective repair method can be prescribed. In some cases, spot testing in the various structural and environmental zones provides sufficient information. In others detailed mapping is required.
The survey results also establish the rate of decay so that an estimate of future deterioration can be made. In some cases, deterioration is relatively unimportant while in others it is critical. We work with associates to provide a structural analysis.
Appropriate Reporting
BCRC pride themselves on their practical approach to consulting. This means that reporting is appropriate to the client’s needs for each project. In some cases, this could mean that the analysis is conveyed to the client along with the survey records. In others, such as litigation fully detailed reports are provided
Benefits of Using BCRC Service
Expert input from durability, concrete, inspection and repair specialist consultants. Inspection is undertaken quickly with pragmatic approach to detailing repairs.
